Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F10/00—Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/18—Manufacture of films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/04—Homopolymers or copolymers of ethene
  • C08L23/08—Copolymers of ethene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
  • C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
  • C08J2323/04—Homopolymers or copolymers of ethene
  • C08J2323/08—Copolymers of ethene

Definitions

• the instant invention relates to an ethylene/alpha-olefin interpolymer suitable for use in shrinkage film applications, and articles made therefrom.
• Ethylene/alpha-olefin interpolymer resins that can make films with improved optical properties (haze, gloss, and/or clarity), puncture properties, and high shrinkage (shrink tension or % free shrink) create high value especially for shrink films, such as collation shrink Films. Additionally, a high modulus is advantageous. It is difficult to obtain a balance of these properties with one resin. For instance, high shrinkage may be obtained by a very high molecular weight. This high molecular weight, however, often results in poor optical properties as very high molecular weight materials tend to be highly elastic and upon extrusion create a high surface roughness on the film leading to lower optical properties. Another example is that generally to increase the modulus the density is increased. When the density is increased, however, the puncture properties generally decrease.
• the ethylene/alpha-olefin interpolymer of the present invention provides good properties (such as optical, puncture, shrinkage, and modulus) without any one of such properties being negatively impacted.
• the instant invention provides an ethylene/alpha-olefin interpolymer suitable for use in shrinkage film applications, and articles made therefrom.
• the instant invention provides an ethylene/alpha-olefin interpolymer, wherein the ethylene/alpha-olefin interpolymer has a CDBI of less than 60%, and wherein said ethylene/alpha-olefin interpolymer comprises at least two fractions in crossfractionation of the ethylene/alpha-olefin interpolymer, eluting from 85°C to 90°C and from 90°C to 95°C, comprising a weight fraction ratio of > 0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95°C and 100°C and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluting between 95°C and 100°C, and wherein said ethylene/alpha- olefin inter
• the instant invention further provides a process to make an ethylene/alpha-olefin interpolymer comprising the steps of contacting ethylene with at least one alpha-olefin under suitable polymerization conditions with a multi -constituent catalyst composition to form an ethylene/alpha-olefin interpolymer, wherein the
• ethylene/alpha-olefin interpolymer has a CDBI of less than 60%, and wherein said ethylene/alpha-olefin interpolymer comprises at least two fractioas in crossfractionation of the ethylene/alpha-olefin interpolymer, eluting from 85°C to 90°C and from 90°C to 95°C, comprising a weight fraction ratio of > 0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95°C and 100°C and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluting between 95°C and 100°C, and wherein said ethylene/alpha-olefin interpolymer has a density in the range of 0.920 to 0.940 g/cm
• the instant invention further provides a blend comprising: less than 100 percent by weight of the ethylene/alpha-olefin interpolymer, as described hereinabove, and greater than or equal to 10 percent by weight of a low density polyethylene composition (LDPE); for example, 35 to 80 percent by weight of the LDPE.
• LDPE low density polyethylene composition
• the instant invention further provides a film comprising an ethylene/alpha-olefin interpolymer, wherein the ethylene/alpha-olefin interpolymer has a CDBI of less than 60%, and wherein said ethylene/alpha-olefin interpolymer comprises at least two fractions in crossfractionation of the ethylene/alpha-olefin interpolymer, eluting from 85°C to 90°C and from 90°C to 95°C, comprising a weight fraction ratio of > 0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95°C and 100°C and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluting between 95 °C and 100°C, and wherein said ethylene/alpha-ole
• the instant invention further provides a film comprising a blend comprising: (a) less than 100 percent by weight of an ethylene/alpha-olefin interpolymer, wherein the ethylene/alpha-olefin interpolymer has a CDBI of less than 60%, and wherein said ethyiene/alpha-olefin interpolymer comprises at least two fractions in crossfractionation of the ethylene/alpha-olefin interpolymer, eluting from 85°C to 90°C and from 90°C to 95°C, comprising a weight fraction ratio of > 0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95°C and 100°C and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluti
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has an average M v and a valley temperature between the low crystalline fraction and high crystalline fraction, T hc , such that the average M v for a fraction above from ATREF divided by average M v of the whole ethylene/alpha-olefin interpolymer from ATREF (M hc /M p ) is less than 1.3.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has a density in the range of from 0.923 to 0.935 g/cm 3 .
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has a melt index in the range of 0.1 to 3 g/10 minutes.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has a melt index in the range of from 0.1 to 1.5 g/10 minutes.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer is heterogeneous ly branched.
• the instant invention provides an ethylene/alpha-oiefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has a CDBI of less than 55%.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has long chain branches less than 1 per 1000 C atoms.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the ethylene/alpha-olefin interpolymer has a molecular weight distribution, M w /M n , of less than about 5.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the film has a MD shrink tension of greater than 25 cN, a haze of less than 10%, and puncture of greater than 170 ft-lb/in 3 .
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the film has a gloss of greater than 65% and a dart impact of greater than 250 g.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the multi-constituent catalyst composition comprises the reaction product of:
• At least one hydrocarbon soluble magnesium component represented by the general formula R" R'Mg.xAlR'3 wherein each R" and R' are alkyl groups;
• reaction temperature does not exceed a temperature in the range of from 20 to 40, for example, it does not exceed about 40° C; or in the alternative, it does not exceed about 35° C;
• Tm is a metal of Groups IVB, VB, V1B, VIIB or VIII of the Periodic Table
• R is a hydrocarbyl group having from 1 to about 20, for example from 1 to about 10 carbon atoms
• X is a halide
• y and x are integers and their sum is equal to 4, and
• additional halide source may be an organo halide compound of Group IIIA metal including, for example, those represented by the formula R' y MX r ; wherein M is a metal from Group IIIA of the Periodic Table of Elements, for example aluminum or boron; each R' is independently an alkyl group having from 1 to 20, for example from 1 to 10, or in the alternative, from 2 to 8, carbon atoms; X is a halogen atom, for example chlorine; y and z each independently have a value from 1 to a value equal to the valence of M.
• R' y MX r organo halide compound of Group IIIA metal including, for example, those represented by the formula R' y MX r ; wherein M is a metal from Group IIIA of the Periodic Table of Elements, for example aluminum or boron; each R' is independently an alkyl group having from 1 to 20, for example from 1 to 10, or in the alternative, from 2 to 8, carbon atoms; X is a hal
• organo halide compounds include, for example, ethylaluminum dichloride, ethylaluminum sequichloride; diethylaiuminum chloride; isobutylaluminum dichloride; diisobutylaluminum chloride; octylaluminum dichloride; and combinations of 2 or more thereof.
• the instant invention provides an ethyl ene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the sum of the weights of all three fractions of polymer eluting between 85°C and 100°C is greater than 60 wt% of the ethyiene/alpha-olefin interpolymer.
• the instant invention provides an ethylene/alpha-olefin interpolymer, blend, method of producing the same, and films made therefrom, in accordance with any of the preceding embodiments, except that the weight average M w of the ethylene/alpha-olefin interpolymer is greater than 125,000 g/mol.
• Fig. 1 is a graph illustrating the dynamic mechanical spectroscopy complex viscosity data versus frequency for Comparative Example 1 and inventive Examples 1 and 2;
• Fig. 2 is a graph illustrating the dynamic mechanical spectroscopy tan delta data versus frequency for Comparative Example 1 and Inventive Examples 1 and 2;
• Fig. 3 is a graph illustrating the dynamic mechanical spectroscopy data of phase angle vs. complex modulus (Van-Gurp Palmen plot) for Comparative Example 1 and Inventive Examples 1 and 2;
• Fig. 4 is a graph illustrating the melt strength data at 190 °C for Comparative Example 1 and Inventive Examples 1 and 2;
• Fig. 5 is a graph illustrating the Conventional GPC data for Comparative Example 1 and Inventive Examples 1 and 2;
• Fig. 6 is a graph illustrating the short chain branching distribution and log M v data from ATREF for Comparative Example 1 and Inventive Examples 1 and 2;
• Fig. 7 is a graph illustrating the Crossfractionation data plotted as the ratio of M w (T)/M w (100 °C) vs. Temperature for Comparative Example 1 and Inventive Examples 1 and 2.
• the instant invention provides an ethylene/alpha-olefin interpolymer suitable for use in shrinkage film applications, and articles made therefrom.
• the inventive ethylene/alpha- olefin interpolymer has a CDBI of less than 60%, and comprises at least two fractions in crossfractionation of the ethylene/alpha-oiefin interpolymer, eluting from 85°C to 90°C and from 90°C to 95°C, comprising a weight fraction ratio of > 0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95°C and I00°C and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluting between 95°C and 100°C.
• the inventive ethylene/alpha-olefin interpolymer has a low melt index ratio (I 10 /I 2 ), and comprises less high molecular weight material in its high crystalline fraction, which can be measured by the ratio of the high crystalline viscosity molecular weight divided by the average viscosity molecular weight of the whole ethylene/alpha-olefin interpolymer, M hc /M p .
• the crossfractionation results indicate that the inventive ethylene/alpha-olefin interpolymer has a more uniform weight average molecular weight for the fractions eluting between 85°C and i00°C.
• This uniformity is expressed by reporting the molecular weight of the lower temperature fractions (85°C and 90°C and 90 a C and 95°C) as a ratio of or relative to the molecular weight of the 95 °C and 100°C fraction, wherein the ratio is greater than 0.65.
• the inventive ethylene/alpha-olefin interpolymer has an average M v and a valley temperature between the low crystalline fraction and high crystalline fraction, T hc , such that the average M v for a fraction above ⁇ hc from ATREF divided by average M v of the whole ethylene/alpha-olefin interpolymer from ATREF (M hc /M p ) is less than 1.3; for example, less than 1.25.
• inventive ethy!ene/alpha-oiefin interpolymers are relatively inhomogeneous (or heterogeneous) ethylene polymers that possess short chain branches and that are
• the inventive ethylene/alpha-olefin interpolymer has a comonomer distribution index (CDBI) in the range of from less than 60%, for example, in the range of from less than 50%, but usually include a measurable high density (high crystalline) polymer fraction.
• CDBI composition distribution breadth index
• the inventive ethylene/alpha-olefin interpolymer has a density in the range of from 0.920 to 0.940 g/cm 3 for example, in the range of from 0.920 to 0.935 g/cm 3 ; or in the alternative, in the range of from 0.923 to 0.935 g/cm 3 .
• the inventive ethylene/alpha-olefin interpolymer has a melt index (I 2 ) in the range of from 0.01 to 5 g/ 10 minutes, for example, in the range of from 0.1 to 3 g/ 10 minutes or in the alternative, in the range of from 0.2 to 2.5 g/ 10 minutes; or in the alternative, in the range of from 0.4 to 2.5 g/ 10 minutes; or in the alternative, in the range of from 0.1 to 1.5 g/ 10 minutes.
• I 2 melt index
• the inventive ethylene/alpha-olefin interpolymer has a melt flow ratio (I 10 /I 2 ) in the range of from less than 9, for example, in the range of from 5 to 9; or in the alternative, in the range of from 5 to 8; or in the alternative, in the range of from 5 to 7.5; or in the alternative, in the range of from 6 to 9; or in the alternative, in the range of from 6 to 8.
• the inventive ethylene/alpha-olefin interpolymer has a molecular weight (M w ) in the range of from greater than 120,000 g/mole, for example, in the range of from 120,000 to 250,000 g/moles.
• the inventive ethylene/alpha-olefin interpolymer has a molecular weight distribution (M w /M n ) (measured according to the conventional GPC method) in the range of from less than 4; for example, less than 3.7; or in the alternative, in the range of from 2.5 to 3.7.
• M w /M n molecular weight distribution
• the inventive ethylene/alpha-olefin interpolymer may comprise less than 20 percent by weight of units derived from one or more ⁇ -olefin comonomers. All individual values and subranges from less than 18 weight percent are included herein and disclosed herein; for example, the inventive ethylene/alpha-olefin interpolymer may comprise less than 15 percent by weight of units derived from one or more ⁇ -olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise less than 10 percent by weight of units derived from one or more ⁇ -olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise from 1 to 20 percent by weight of units derived from one or more a-olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise from 1 to 10 percent by weight of units derived from one or more
• the inventive ethylene/alpha-olefin interpolymer may comprise less than 10 percent by moles of units derived from one or more a-olefin comonomers. Ail individual values and subranges from less than 10 mole percent are included herein and disclosed herein; for example, the inventive ethylene/alpha-olefin interpolymer may comprise less than 7 percent by moles of units derived from one or more ⁇ -olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise less than 4 percent by moles of units derived from one or more ⁇ -olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise less than 3 percent by moles of units derived from one or more ⁇ -olefin comonomers; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise from 0.5 to 10 percent by moles of
• the ⁇ -olefin comonomers typically have no more than 20 carbon atoms.
• the a-olefin comonomers may preferably have 3 to 10 carbon atoms, and more preferably 3 to 8 carbon atoms.
• Exemplary ⁇ -olefin comonomers include, but are not limited to, propylene, 1-butene, 1-pentene, 1-hexene, I-heptene, 1-octene, l-nonene, 1-decene, and 4-methyl-l-pentene.
• the one or more ⁇ -olefin comonomers may, for example, be selected from the group consisting of propylene, 1-butene, 1-hexene, and 1-octene; or in the alternative, from the group consisting of 1-hexene and 1-octene.
• the inventive ethylene/alpha-olefin interpolymer may comprise at least 80 percent by weight of units derived from ethylene. All individual values and subranges from at least 80 weight percent are included herein and disclosed herein; for example, the inventive ethylene/alpha-olefin interpolymer may comprise at least 82 percent by weight of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise at least 85 percent by weight of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise at least 90 percent by weight of units derived from ethylene; or in the alternative, the inventive ethylene/alpha- olefin interpolymer may comprise from 80 to 99 percent by weight of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise from 90 to 99 percent by weight of units derived from ethylene.
• the inventive ethylene/alpha-olefin interpolymer may comprise at least 90 percent by moles of units derived from ethylene. All individual values and subranges from at least 90 mole percent are included herein and disclosed herein; for example, the inventive ethylene/alpha-olefin interpolymer may comprise at least 93 percent by moies of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise at least 96 percent by moles of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise at least 97 percent by moies of units derived from ethylene; or in the alternative, the inventive ethylene/alpha- olefin interpolymer may comprise from 90 to 99.5 percent by moles of units derived from ethylene; or in the alternative, the inventive ethylene/alpha-olefin interpolymer may comprise from 97 to 99.5 percent by moles of units derived from ethylene.
• Any conventional polymerization processes may be employed to produce the inventive ethylene/alpha-olefin interpolymers.
• Such conventional polymerization processes include, but are not limited to, solution polymerization process, gas phase polymerization process, slurry phase polymerization process, and combinations thereof using one or more conventional reactors e.g. loop reactors, isothermal reactors, fluidized bed gas phase reactors, stirred tank reactors, batch reactors in parallel, series, and/or any combinations thereof.
• inventive ethylene/alpha-olefin interpolymer may, for example, be produced via solution-phase polymerization process using one or more loop reactors, isothermal reactors, and combinations thereof.
• the solution phase polymerization process occurs in one or more well- stirred reactors such as one or more loop reactors or one or more spherical isothermal reactors at a temperature in the range of from 150 to 300 °C; for example, from 160 to 190 °C, and at pressures in the range of from 300 to 1000 psi; for example, from 400 to 750 psi.
• the residence time in solution phase polymerization process is typically in the range of from 2 to 30 minutes; for example, from 10 to 20 minutes.
• Ethylene, solvent, multi-constituent catalyst composition, and optionally one or more comonomers are fed continuously to the reactor.
• Exemplary multi-constituent catalyst compositions in these embodiments include, for example, Ziegler-Natta catalysts, as described herein.
• Exemplary solvents include, but are not limited to, isoparaffins.
• such solvents are commercially available under the name 1SOPAR E from ExxonMobil Chemical Co., Houston, Texas.
• the resultant mixture of the inventive ethylene/alpha-olefin interpolymer and solvent is then removed from the reactor and the inventive ethylene/alpha-olefin interpolymer is isolated.
• Solvent is typically recovered via a solvent recovery unit, i.e. heat exchangers and vapor liquid separator drum, and is then recycled back into the polymerization system.
• Low reactor temperature is a requirement of the present invention and is important in facilitating the narrowing of the molecular weight distribution.
• Reactor temperature of 175°C yielded a product with narrow molecular weight distribution without significantly reducing the production output (Ib/hr).
• inventive ethylene/alpha-olefin interpolymer may be prepared using a multi-constituent catalyst composition, as described herein, suitable for
• the solvent and comonomer ( I -octene) feed is pressurized via a mechanical positive displacement pump to a pressure that is above the reaction pressure, e.g. 750 psig.
• the individual catalyst components are manually batch diluted to specified component concentrations with purified solvent (ISOPAR E) and pressured to a pressure that is above the reaction pressure, e.g. 750 psig. All reaction feed flows are measured with mass flow meters and independently controlled with computer automated valve control systems.
• the continuous solution polymerization reactor may consist of a liquid full, non- adiabatic, isothermal, circulating, loop. Independent control of all fresh solvent, monomer, comonomer, hydrogen, and catalyst component feeds is possible.
• the combined solvent, monomer, comonomer and hydrogen feed is temperature controlled to anywhere between 5°C to 50°C and typically 40°C by passing the feed stream through a heat exchanger.
• the fresh comonomer feed to the polymerization reactor is aligned to add comonomer to the recycle solvent.
• the total fresh feed to the polymerization reactor is injected into the reactor at, for example, two locations roughly with equal reactor volumes between each injection location.
• the fresh feed is controlled typically with each injector, for example, receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through, for example, a specially designed injection inlet device and are combined into one mixed procatalyst/cocatalyst feed stream prior to injection into the reactor.
• the procatalyst component feed is computer controlled to maintain the reactor monomer concentration at a specified target.
• the cocatalyst component is fed based on calculated specified molar ratios to the procatalyst component Immediately following each fresh injection location (either feed or catalyst), the feed streams are mixed with the circulating polymerization reactor contents with static mixing elements such as Kenics static mixing elements.
• the contents of the reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around the reactor loop can be provided by a screw pump.
• the effluent from the polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst components, and molten polymer) exits the reactor loop and enters a zone where it is contacted with a deactivating and acid scavenging agent (typically calcium stearate and the accompanying water of hydration) to stop the reaction and scavenge hydrogen chloride.
• a deactivating and acid scavenging agent typically calcium stearate and the accompanying water of hydration
• various additives such as antioxidants can be added at this point.
• the stream then goes through another set of static mixing elements such as Kenics static mixing elements to evenly disperse the catalyst kill and additives.
• the effluent (containing solvent, monomer, comonomer, hydrogen, catalyst components, and molten polymer) passes through a heat exchanger to raise the stream temperature in preparation for separation of the polymer from the other lower boiling reaction components.
• the stream then passes through a pressure let down control valve, which is responsible for maintaining the pressure of the reactor at a specified target.
• the stream then enters a two stage separation and devolatilization system where the polymer is removed from the solvent, hydrogen, and unreacted monomer and comonomer. Impurities are removed from the recycled before entering the reactor again.
• the separated and devolatilized polymer melt is, for example, pumped through a die specially designed for underwater pelletization, cut into uniform solid pellets, dried, and transferred into a hopper. After validation of initial polymer properties, the solid polymer pellets are transferred to storage devices.
• the portions removed in the devolatilization step may be recycled or destroyed.
• most of the solvent is recycled back to the reactor after passing through purification beds.
• This recycled solvent can still have unreacted co-monomer in it that is fortified with fresh co-monomer prior to re-entry to the reactor.
• This recycle solvent can still have some hydrogen which is then fortified with fresh hydrogen.
• the inventive ethylene/alpha-olefin interpolymer may be prepared using a multi-constituent catalyst system, as described herein, suitable for (co)polymerizing ethylene and one or more a-olefin comonomers, e.g.
• 1-octene via a solution phase polymerization process in two adiabatic spherical reactors, linked together in series in accordance to the following procedure.
• the ethylene monomer, 1-octene comonomer, and hydrogen are combined with a solvent, e.g. an isoparaffinic solvent such as ISOPAR E.
• Impurities such as water, carbon dioxide, sulfurous compounds are removed from the feed streams, and the feed streams are cooled to temperature in the range of 5° C to 60° C, for example, approximately 13°C, before entering the reactor.
• the majority, approximately from 85 to 90 percent, of the reaction may occur in the first spherical reactor.
• the mixing may be achieved via circulating the polymer/procatalyst/cocatalyst/solvent/ethylene/co- monomer/hydrogen solution with one or more agitators equipped with mixing blades.
• the feed ethylene/comonomer/solvent/hydrogen
• the first reactor temperature is in the range of from 160° C to 190° C, for example, approximately 175°C
• the reactor pressure is in the range of from 400 psi to 1000 psi, for example, approximately 500 psi.
• the temperature of the second reactor, in series with the first increases to a temperature in the range of from 175° C to 210° C, for example, approximately 202° C with approximately from 10 to 15 percent of the remaining reaction occurring and no additional catalyst or monomers are added.
• Procatalyst/Co-catalyst A1/Ti molar feed ratio is set at value in the range of 0.5: 1 to 3: 1.
• the average reactor residence time is in the range of from 2 to 30 minutes, for example, approximately 8 minutes per spherical reactor prior to termination post-reactor by a fluid specially designed for that purpose.
• the solvent with unconverted ethylene monomer and 1-octene comonomer may be removed from the polymer solution via a two stage devolatilizer system, and then recycled. Impurities may be removed from the recycled stream before entering the reactor again.
• the polymer melt may, for example, be pumped through a die specially designed for underwater pelletization. The pellets are transferred to classifier screens to remove over and undersize particles. The Finished pellets are then transferred to storage devices.
• the multi-constituent catalyst system includes a Ziegler-Natta catalyst composition including a magnesium and titanium containing procatalyst and a cocatalyst.
• the procatalyst is a Ziegler Natta catalyst including a titanium compound supported on MgCl 2 .
• the cocatalyst is a triethylaluminum.
• the procatalyst may have a Ti:Mg ratio between ⁇ .0:40 to 5,0:40, for example, 3.0:40.
• the procatalyst and the cocatalyst components can be contacted either before entering the reactor or in the reactor.
• the procatalyst may, for example, be any other titanium based Ziegler Natta catalyst.
• the AI:Ti molar ratio of cocatalyst component to procatalyst component can be from 0.5: 1 to 3: 1.
• Low Al/Ti ratio is important because it facilitates the narrowing of the molecular weight distribution and the lowering of the melt flow ratio ⁇ 10 / ⁇ 2 ⁇
• the multi-constituent catalyst composition with a Ti:Mg ratio between 1.0:40 to 5.0:40, for example, 3.0:40, an Al/Ti ratio of in the range of from 0.5: 1 to 3: 1 have yielded a product with narrow molecular weight distribution, low melt flow ratio I10/I2 without significantly affecting reactor stability.
• the multi-constituent catalyst system includes a Ziegler-Natta catalyst composition including a magnesium and titanium containing procatalyst and a cocatalyst.
• the procatalyst may, for example, comprise the reaction product of magnesium dichloride, an alkylaluminum dihalide, and a titanium alkoxide.
• the procatalyst comprises the reaction product of:
• At least one hydrocarbon soluble magnesium component represented by the general formula R" R'Mg.xAIR'3 wherein each R" and R' are alkyl groups;
• reaction temperature does not exceed a temperature in the range of from 20 to 40, for example, it does not exceed about 40° C; or in the alternative, it does not exceed about 35° C;
• Tm is a metal of Groups IVB, VB, VIB, VIIB or VIII of the Periodic Table
• R is a hydrocarbyl group having from 1 to about 20, for example from I to about 10 carbon atoms
• X is a halide
• y and x are integers and their sum is equal to 4, and
• additional halide source may be an organo halide compound of Group ⁇ metal including, for example, those represented by the formula R' y MX z ; wherein M is a metal from Group ⁇ of the Periodic Table of Elements, for example aluminum or boron; each R' is independently an alkyl group having from 1 to 20, for example from 1 to 10, or in the alternative, from 2 to 8, carbon atoms; X is a halogen atom, for example chlorine; y and z each independently have a value from 1 to a value equal to the valence of M.
• R' y MX z organo halide compound of Group ⁇ metal including, for example, those represented by the formula R' y MX z ; wherein M is a metal from Group ⁇ of the Periodic Table of Elements, for example aluminum or boron; each R' is independently an alkyl group having from 1 to 20, for example from 1 to 10, or in the alternative, from 2 to 8, carbon atoms; X is a hal
• organo halide compounds include, for example, ethylaluminum dichloride, ethylaluminum sequichloride; diethylaluminum chloride; isobutylaluminum dichloride; diisobutylaluminum chloride; octylaluminum dichloride; and combinations of 2 or more thereof.
• transition metal compounds include, for example, titanium tetrachloride, titanium trichloride, tetra(isopropoxy)-titanium, tetrabutoxy titanium, diethoxytitanium dibromide, dibutoxytitanium dichloride, tetraphenoxytitanium, tri- isopropoxy vanadium oxide, zirconium tetra-n-propoxide, mixtures thereof and the like.
• procatalyst components are combined in proportions sufficient to provide atomic ratios as previously mentioned.
• the foregoing pro-catalytic reaction product is prepared in the presence of an inert diluent.
• concentrations of catalyst components are such that when the essential components of the catalytic reaction product are combined, the resultant slurry is from about 0.005 to about 1.0 molar (moles/liter) with respect to magnesium.
• Exemplary suitable inert organic diluents include, but are not limited to, liquefied ethane, propane, isobutane, n- butane, n-hexane, the various isomeric hexanes, isooctane, paraffinic mixtures of alkanes having from 8 to 12 carbon atoms, cyclohexane, methylcyclopentane, dimethylcyclohexane, dodecane, industrial solvents composed of saturated or aromatic hydrocarbons such as kerosene, and naphthas.
• Exemplary suitable inert organic diluents are free of any olefin compounds and other impurities.
• Exemplary suitable inert organic diluents have boiling points in the range of from -50 °C to 200 °C.
• Mixing of the procatalyst components to provide the desired catalytic reaction product is advantageously prepared under an inert atmosphere such as nitrogen, argon or other inert gas at temperatures in the range of from 10° C to 50° C; for example, from 20° C to 40° C, provided that the magnesium halide support is prepared such that the reaction temperature does not exceed 35° C.
• an inert atmosphere such as nitrogen, argon or other inert gas at temperatures in the range of from 10° C to 50° C; for example, from 20° C to 40° C, provided that the magnesium halide support is prepared such that the reaction temperature does not exceed 35° C.
• the procatalyst composition serves as one component of a Ziegler-Narta catalyst composition, in combination with a cocatalyst.
• the cocatalyst is employed in a molar ratio based on titanium in the procatalyst of from 1 : 1 to 100: 1 ; for example, in a molar ratio in the range of from 0.5: 1 to 3: 1.
• the inventive ethylene/alpha-olefin interpolymer may be blended with one or more polymers, for example a low density polyethylene composition, to form a blend.
• a low density polyethylene composition may have a density in the range of from 0.910 g/cm 3 to 0.940 g/cm 3 ; for example, from 0.915 g/cm 3 to 0.935 g/cm 3 , and a melt index (I 2 ) in the range of from 0.1 to 5 g/10 minutes; for example, from 0.2 to 2g/10 minutes.
• the blend may have a density in the rage of from 0.910 g/cm 3 to 0.940 g/cm 3 ; for example, from 0.915 g/cm 3 to 0.935 g/cm 3 , and a melt index (I 2 ) in the range of from 0.05 to 5 g/10 minutes; for example, from 0.1 to 2 g/10 minutes.
• the inventive ethylene/alpha-olefin interpolymer may be blended with one or more additives.
• additives include, but are not limited to, antistatic agents, color enhancers, dyes, lubricants, fillers, pigments, primary antioxidants, secondary antioxidants, processing aids, UV stabilizers, and combinations thereof.
• the blend of the inventive ethylene/alpha- olefin interpolymer with one or more additives may contain any amounts of additives.
• the blend of the inventive ethylene/alpha-olefin interpolymer and one or more additives may compromise from about 0 to about 10 percent by the combined weight of such additives, based on the weight of the inventive ethylene/alpha-olefin interpolymer and the one or more additives.
• the inventive ethylene/alpha-olefin interpolymer or blend thereof with one or more other polymers may be used to manufacture films.
• films may include, but are not limited to, clarity shrink films, collation shrink films, cast stretch films, silage films, stretch hooder films, sealants, stand up pouch films, liner films, machine direction oriented films, and diaper backsheets.
• Suitable conversion techniques include, but are not limited to, blown film process, cast film process, tenter frame process, double bubble process, such as partially crosslinked or non-cross linked, vertical or horizontal form fill and seal process. Such techniques are generally well known.
• the conversion technique includes, but is not limited to, the blown film process.
• the films according to the present invention may include at least one film layer, such as a monolayer film, or at least one layer in a multilayer film prepared by cast, blown, calendered, or extrusion coating processes.
• the inventive ethylene/alpha-olefin interpolymer or blend thereof with one or more other polymers, for example LDPE may be used in a variety of films, including but not limited to clarity shrink films, collation shrink films, cast stretch films, silage films, stretch hooder films, sealants, stand up pouch films, liner films, machine direction oriented films, and diaper backsheets.
• the inventive films have a MD shrink tension of greater than 25 cN, for example, 15 cN to 40 cN; a haze of less than 10%, for example, 5% to 15%; and puncture of greater than 170 ft-lb/in 3 , for example, 150 ft-lb/in 3 to 400 ft-lb/in 3
• All raw materials ethylene, 1-octene
• the process solvent an isoparaffinic solvent under the tradename ISOPAR E, which is commercially available from ExxonMobil Corporation
• Hydrogen is supplied in pressurized cylinders as a high purity grade and is not further purified.
• the reactor monomer feed (ethylene) stream is pressurized via a mechanical compressor to a pressure that is above the reaction pressure, e.g. 750 psig.
• the solvent and comonomer (1-octene) feed is pressurized via a mechanical positive displacement pump to pressure that is above the reaction pressure, e.g. 750 psig.
• the individual catalyst components are manually batch diluted to specified component concentrations with purified solvent (ISOPAR E) and pressured to a pressure that is above the reaction pressure, e.g. 750 psig. All reaction feed flows are measured with mass flow meters and independently controlled with computer automated valve control systems.
• ISOPAR E purified solvent
• the continuous solution polymerization reactor consists of a liquid full, non-adiabatic, isothermal, circulating, loop. Independent control of all fresh solvent, monomer,
• the combined solvent, monomer, comonomer and hydrogen feed is temperature controlled to anywhere between 5° C to 50° C and typically 40° C by passing the feed stream through a heat exchanger.
• the fresh comonomer feed to the polymerization reactor is aligned to add comonomer to the recycle solvent.
• the total fresh feed to the polymerization reactor is injected into the reactor at two locations roughly with equal reactor volumes between each injection location.
• the fresh feed is controlled typically with each injector receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through a specially designed injection inlet device and are combined into one mixed
• procatalyst/cocatalyst feed stream prior to injection into the reactor prior to injection into the reactor.
• the cocatalyst component is fed based on calculated specified molar ratios to the procatalyst component.
• the feed streams are mixed with the circulating polymerization reactor contents with Kenics static mixing elements.
• the contents of the reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around the reactor loop is provided by a screw pump.
• the effluent from the polymerization reactor exits the reactor loop and enters a zone where it is contacted with a deactivating and acid scavenging agent (typically calcium stearate and the accompanying water of hydration) to stop the reaction and scavenge hydrogen chloride.
• a deactivating and acid scavenging agent typically calcium stearate and the accompanying water of hydration
• various additives such as antioxidants can be added at this point.
• the stream then goes through another set of Kenics static mixing elements to evenly disperse the catalyst kill and additives.
• the effluent (containing solvent, monomer, comonomer, hydrogen, catalyst components, and molten polymer) passes through a heat exchanger to raise the stream temperature in preparation for separation of the polymer from the other lower boiling reaction components.
• the stream then passes through a pressure let down control valve (responsible for maintaining the pressure of the reactor at a specified target).
• the stream then enters a two stage separation and devolatilization system where the polymer is removed from the solvent, hydrogen, and unreacted monomer and comonomer. Impurities are removed from the recycled stream before entering the reactor again.
• the separated and devoiatilized polymer melt is pumped through a die specially designed for underwater pelletization, cut into uniform solid pellets, dried, and transferred into a hopper. After validation of initial polymer properties, the solid polymer pellets are transferred to storage devices.
• the portions removed in the devolatilization step may be recycled or destroyed.
• most of the solvent is recycled back to the reactor after passing through purification beds.
• the recycled solvent can still have unreacted co-monomer in it that is fortified with fresh co-monomer prior to re-entry to the reactor.
• the recycled solvent can still have some hydrogen which is then fortified with fresh hydrogen.
• Tables 1- 3 summarize conditions for polymerization of Comparative Example 1 and Inventive Examples 1 and 2. Additives used in Comparative Example 1 and Inventive Examples 1 and 2 were 1250 ppm calcium stearate, 1000 ppm Irgafos 168, 250 ppm Irganox 1076, and 200 ppm Irganox 1010.
• Table 3 Catalyst conditions used to make Comparative Example 1 and Inventive Examples 1 and 2 in which TEA is tri-ethyl aluminum.
• ATREF data are summarized in Table 1 1 and Figure 6 for Comparative Example 1 and Inventive Example 1 and 2.
• the calculated molecular weights are derived from the weight fraction, w T , and intrinsic viscosity, [ ⁇ ] T , measured at each elution temperature, T, in the ATREF analysis.
• the viscosity average molecular weight, M V , T is first calculated from each intrinsic viscosity as follows:
• the average molecular weights are then calculated as follows:
• the different temperature ranges applied to each average are T hc to 1 10°C for M hc , 60° to 90°C for M c-1 , and 75° to 90°C for M c-2 , and 20° to 1 10°C for M P .
• Table 11 Resin product and characterization data including ATREF data for Comparative Example 1 and Inventive Examples 1 and 2
• PPA polymer processing aid
• Inventive Film 1 comprises the ethylene/alpha-olefin interpolymer of Inventive Example I .
• Inventive Film 2 comprises ethylene/alpha-olefin interpolymer of the Inventive Example 2.
• Inventive Film 3 comprises a blend comprising 65 percent by weight of the ethylene/alpha-olefin interpolymer of the Inventive Example 1 and 35 percent by weight of a high pressure low density polyethylene, Dow high pressure low density polyethylene (LDPE) LDPE 1321 (0.25 MI, 0.921 g/cm 3 ).
• LDPE Dow high pressure low density polyethylene
• Inventive Film 4 comprises a blend comprising 65 percent by weight of the ethylene/alpha-olefin interpolymer of the Inventive Example 2 and 35 percent by weight of a high pressure low density polyethylene, Dow high pressure low density polyethylene (LDPE) LDPE 1321 (0.25 MI, 0.921 g/cm 3 ).
• LDPE Dow high pressure low density polyethylene
• Comparative Film 1 comprises the ethylene polymer of Comparative Example 1.
• Comparative Film 2 comprises a blend comprising 65 percent by weight of the polymer of the Comparative Example 1 and 35 percent by weight of a high pressure low density polyethylene, Dow high pressure low density polyethylene (LDPE) LDPE 1321 (0.25 MI, 0.921 g/cm 3 ).
• LDPE Dow high pressure low density polyethylene
• Comparative Films 1-2 are shown in Table 15.
• the temperatures in Table 15 show the temperatures closest to the pellet hopper (Barrel 1) and in increasing order as the polymer is being extruded through the die (upper die).
• the film properties are reported in Table 16-17.
• Table 15 Blown film process parameters used to produce Inventive Films 1-4 and
• Test methods include the following:
• Density (g/cm 3 ) is measured according to ASTM-D 792-03, Method B, in isopropanol. Specimens are measured within 1 hour of molding after conditioning in the isopropanol bath at 23 ° C for 8 min to achieve thermal equilibrium prior to measurement. The specimens are compression molded according to ASTM D-4703-00 Annex A with a 5 min initial heating period at about 190 ° C and a 15 ° C/min cooling rate per Procedure C. The specimen is cooled to 45 ° C in the press with continued cooling until "cool to the touch.”
• Melt index or h is measured in accordance with ASTM D 1238, Condition 190 °C/2.16 kg, and is reported in grams eluted per 10 minutes.
• I 10 is measured in accordance with ASTM D 1238, Condition 190 °C/10 kg, and is reported in grams eluted per 10 minutes.
• CDBI Comonomer Distribution Breadth Index
• the CDBI is defined as the weight percent of the polymer molecules having a comonomer content within 50 percent of the median total molar co-monomer content and represents a comparison of the co-monomer distribution in the polymer to the co-monomer distribution expected for a Bernoullian distribution.
• the CDBI of polyolefins can be
• TREF' temperature rising elution fractionation
• TREF' temperature rising elution fractionation
• the TREF technique does not include purge quantities in CDBI calculations.
• the co- monomer distribution of the polymer is determined using C NMR analysis in accordance with techniques described, for example, in U.S. Patent No. 5,292,845 (Kawasaki, et al.) and by J. C. Randall in Rev. Macromol. Chem. Phys., C29, 201-317. Presence of Long Chain Branching
• the presence of long chain branching can be determined in ethylene homopolymers by using l 3 C nuclear magnetic resonance (NMR) spectroscopy and is quantified using the method described by Randall (Rev. Macromol. Chem, Phys., C29, V. 2&3, 285-297).
• NMR nuclear magnetic resonance
• Two such exemplary methods are gel permeation chromatography coupled with a low angle laser light scattering detector (GPC- LALLS) and gel permeation chromatography coupled with a differential viscometer detector (GPC-DV). The use of these techniques for long chain branch detection and the underlying theories have been well documented in the literature.
• Differential Scanning Calorimetry can be used to measure the melting and crystallization behavior of a polymer over a wide range of temperature.
• the TA Instruments Q1000 DSC equipped with an RCS (refrigerated cooling system) and an autosampler is used to perform this analysis.
• RCS refrigerated cooling system
• a nitrogen purge gas flow of 50 rmVmin is used.
• Each sample is melt pressed into a thin film at about 175 °C; the melted sample is then air-cooled to room temperature (-25 °C).
• a 3-10 mg, 6 mm diameter specimen is extracted from the cooled polymer, weighed, placed in a light aluminum pan (ca 50 mg), and crimped shut. Analysis is then performed to determine its thermal properties.
• the thermal behavior of the sample is determined by ramping the sample temperature up and down to create a heat flow versus temperature profile. First, the sample is rapidly heated to 180 °C and held isothermal for 3 minutes in order to remove its thermal history. Next, the sample is cooled to -40 °C at a 10 °C/minute cooling rate and held isothermal at -40 °C for 3 minutes. The sample is then heated to 150 °C (this is the "second heat" ramp) at a 10 °C/minute heating rate. The cooling and second heating curves are recorded. The cool curve is analyzed by setting baseline endpoints from the beginning of crystallization to -20 °C. The heat curve is analyzed by setting baseline endpoints from -20 °C to the end of melt.
• % Crystallinity ((H f )/(292 J/g)) x 100
• the chromatographic system consisted of a Polymer Laboratories Model PL-220. The column and carousel compartments were operated at 140 °C. Three Polymer Laboratories ⁇ - ⁇ Mixed-B columns were used with a solvent of 1 ,2,4 trichlorobenzene. The samples were prepared at a concentration of 0.1 g of polymer in 50 ml of solvent. The solvent used to prepare the samples contained 200 ppm of the antioxidant butylated hydroxytoluene (BHT). Samples were prepared by agitating lightly for 4 hours at 160 °C. The injection volume used was 100 microliters and the flow rate was 1.0 mi/min.
• BHT antioxidant butylated hydroxytoluene
• M polyethylene A (M polystyrene ) B in which M is the molecular weight, A has a value of 0.4316 and B is equal to 1.0.
• Polyethylene equivalent molecular weight calculations were performed using Viscotek TriSEC software Version 3.0. Williams, T., and I.M. Ward, "The Construction of Polyethylene Calibration Curve for Gel Permeation Chromatography Using Polystyrene Fractions", J. Polym. Sci. Polym. Lett., 6, 621 (1968).
• ATREF analytical temperature rising elution fractionation analysis
• trichlorobenzene and allowed to crystallize in a column containing an inert support (stainless steel shot) by slowly reducing the temperature to 20 °C at a cooling rate of 0.1 °C/min.
• the column is equipped with an infrared detector.
• An ATREF chromatogram curve is then generated by eluting the crystallized polymer sample from the column by slowly increasing the temperature of the eluting solvent (trichlorobenzene) from 20 to 120 °C at a rate of 1.5 °C/min. Viscosity average molecular weight (M v ) of the eluting polymer is measured and reported.
• An ATREF plot has the short chain branching distribution (SCBD) plot and a molecular weight plot.
• the SCBD plot has 3 peaks, one for the high crystalline fraction (typically above 90°C), one for copolymer fraction (typically in between 30-90°C) and one for purge fraction (typically below 30°C).
• the curve also has a valley in between the copolymer and the high crystalline fraction.
• T hc is the lowest temperature in this valley.
• % High density (HD) fraction is the area under the curve above T hc .
• M v is the viscosity average molecular weight from ATREF.
• M hc is the average M v for fraction above T hc - Mc is the average M v of copolymer between 60-90°C.
• M p is the average M v of whole polymer.
• Resins were compression-molded into 3 mm thick x 1 inch circular plaques at 350°F for 5 minutes under 1500 psi pressure in air. The sample is then taken out of the press and placed on the counter to cool.
• a constant temperature frequency sweep is performed using a TA Instruments
• Melt strength is measured at 190 °C using a Goettfert Rheotens 71.97 (Goettfert Inc.; Rock Hill, SC), melt fed with a Goettfert Rheotester 2000 capillary rheometer equipped with a flat entrance angle (180 degrees) of length of 30 mm and diameter of 2 mm.
• the extrudate passes through the wheels of the Rheotens located at 100 mm below the die exit and is pulled by the wheels downward at an acceleration rate of 2.4 mm/s".
• the force (in cN) exerted on the wheels is recorded as a function of the velocity of the wheels (in mm/s). Melt strength is reported as the plateau force (cN) before the strand broke.
• the experiment is performed with an instrument constructed according to Gillespie and Li Pi Shan et al. (Apparatus for Method for Polymer Characterization, WO2006081 116).
• the data acquisition rate is one data point/second.
• the TREF columns are constructed from acetone-washed l/8inch x 0.085inch 316 stainless steel tubing.
• the tubing is cut to a length of 42 inches and packed with a dry mixture (60:40 volume: volume) of pacified 316 stainless steel cut wire of 0.028 inch diameter (Pellet Inc., North Tonawanda, NY) and 30-40 mesh spherical technical grade glass beads.
• This combination of column length and packing material results in an interstitial volume of approximately 1.75 mL.
• the TREF column ends are capped with Valco microbore HPLC column end fittings equipped with a 10 ⁇ stainless steel screen. These column ends provide the TREF columns with a direct connection to the plumbing of the cross fractionation instrument within the TREF oven.
• the TREF columns are coiled, outfitted with a resistance temperature detector (RTD) temperature sensor, and wrapped with glass insulation tape before installation. During installation, extra care is given to level placement of the TREF column with the oven to ensure adequate thermal uniformity within the column. Chilled air is provided at 40 L/min to the TREF ovens via a chiller whose bath temperature is 2 °C. TREF column temperature calibration
• sample solutions are prepared as 4 mg/niL solutions in 1,2,4-trichlorobenzene (TCB) containing 180ppm butylated hydroxytoluene (BHT) and the solvent is sparged with nitrogen. A small amount of decane is added as a flow rate marker to the sample solution for GPC elution validation. Dissolution of the samples is completed by gentle stirring at 145°C for four hours.
• Samples are injected via a heated transfer line to a fixed loop injector (Injection loop of 500 ⁇ ) directly onto the TREF column at 145°C.
• the column After the sample has been injected onto the TREF column, the column is taken "off-line” and allowed to cool.
• the temperature profile of the TREF column is as follows: cooling down from 145°C to 110°C at 2.19°C/min, cooling down from 110°C to 30°C at 0.110 o C/irun, and thermal equilibrium at 30°C for 16 minutes.
• the column is placed back "on-line” to the flow path with a pump elution rate of 0.9 mi/min for 1.0 minute.
• the heating rate of elution is 0.119°C/min from 30°C to 110°C.
• the 16 fractions are collected from 30°C to 1 10°C at 5 L 'C increments per fraction. Each fraction is injected for GPC analysis. Each of the 16 fractions are injected directly from the TREF column over a period of 1.0 minute onto the GPC column set. The eluent is equilibrated at the same temperature as the TREF column during elution by using a temperature pre- equilibration coil (Gillespie and Li Pi Shan et al., Apparatus for Method for Polymer
• Fraction (105°C) represent the amount of material eluting from the TREF column with a temperature range of 30.01 to 35°C, 35.01 to 40°C, 40.01 to 45°C, 45.01 to 50°C, 50.01 to 55°C, 55.01 to 60°C, 60.01 to 65°C, 65.01 to 70°C, 70.01 to 75°C, 75.01 to 80°C, 80.01 to 85°C, 85.01 to 90°C, 90.01 to 95°C, 95.01 to 100°C, and 100.01 to 105°C, respectively.
• the cross fractionation instrument is equipped with one 20 ⁇ m guard column and four Mixed A-LS 20 ⁇ m columns (Varian Inc., previously PolymerLabs), and the IR-4 detector from PolymerChar (Spain) is the concentration detector.
• the GPC column set is calibrated by running twenty one narrow molecular weight distribution polystyrene standards.
• the molecular weight (MW) of the standards ranges from 580 to 8,400,000 g/mol, and the standards are contained in 6 "cocktail" mixtures. Each standard mixture (“cocktail”) has at least a decade of separation between individual molecular weights.
• the standards are purchased from Polymer Laboratories (Shropshire, UK).
• the polystyrene standards are prepared at 0.005 g in 20 mL of solvent for molecular weights equal to or greater than 1,000,000 g/mol and 0.001 g in 20 mL of solvent for molecular weights less than 1,000,000 g/mol.
• the polystyrene standards are dissolved at 145°C with gentle agitation for 30 minutes.
• the narrow standards mixtures are run first and in the order of decreasing highest molecular weight component to minimize
• a logarithmic molecular weight calibration is generated using a fourth-order polynomial fit as a function of elution volume.
• the polystyrene standard peak molecular weights are converted to polyethylene molecular weights using the following equation as described in Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968):
• M polyethylene A (M polystyrene ) B where M is the molecular weight. A has a value of 0.40 and B is equal to 1.0.
• the plate count for the four Mixed A-LS 20 pm columns needs to be at least 19,000 by using a 200 ⁇ injection volume of a 0.4 mg/ml solution of Eicosane in 1,2,4-Trichlorobenzene (TCB) bypassing the TREF column.
• the plate count calculates from the peak retention volume (RV pk m ax ) and the retention volume (RV) width at 1 ⁇ 2 height (50% of the chromatographic peak) to obtain an effective measure of the number of theoretical plates in the column by using the following equation (Striegel and Yau et al., "Modern Size-Exclusion Liquid Chromatography", Wiley, 2009, Page 86):
• the molecular weight distribution (MWD) of each fraction is calculated from the integrated GPC chromatogram to obtain the weight average molecular weight for each fraction, MW(Temperature) .
• the establishment of the upper integration limit is based on the visible difference between the peak rise from the baseline.
• the establishment of the lower integration limit is viewed as the return to the baseline or the point of the elution volume of the polystyrene narrow molecular weight standard of 3250 molecular weight (whichever is earlier).
• the white noise level of the IR-4 detector is calculated from the IR-4 detector upon analyzing the GPC chromatogram before the upper integration limit (prior to polymer elution).
• the detector response at each acquisition time contributed from the polymer chains is first corrected for the baseline correction to obtain the baseline subtracted signal (IR(RV), RV is the elution volume of the GPC chromatogram).
• the baseline corrected IR-4 response is further corrected for white noise: FR(RV) is used in the GPC calculation only if IR(RV) is larger than the white noise value.
• a typical white noise for the IR is determined to be 0.35 raV while the whole-polymer (direct 0.50 mg GPC-injection on the GPC column bypassing the TREF column) peak height in mV is typically around 240 for a polyolefm polymer (high density polyethylene, polydispersity M w /M n approximately 2.6). Care should be maintained to provide a signal to noise ratio (the peak height of whole polymer injection to the white noise) of at least 500 at 1.0 mg/ml 500jiL injection volume for a polyolefm polymer (high density polyethylene, polydispersity ⁇ / ⁇ ⁇ approximately 2.6).
• the area of each individual GPC chromatogram corresponds to the amount of polyoiefmic material eluted from the TREF fraction.
• the weight percentage of the TREF fraction at a specified temperature range of the Fraction, Wt%(Temperature), is calculated as the area of the individual GPC chromatogram divided by the sum of the areas of the 16 individual GPC chromatograms.
• the GPC molecular weight distribution calculations (Mn, Mw, and Mz) are performed on each chromatogram and reported only if the weight percentage of the TREF fraction is larger than 1.0wt%, The GPC weight-average molecular weight, Mw, is reported as M W (Temperature) of each chromatogram.
• Wt% (30°C) represents the amount of material eluting from the TREF column at 30°C during the TREF elution process.
• the highest temperature fraction molecular weight, MW (Highest Temperature Fraction), is defined as the molecular weight calculated at the highest temperature containing more than 1.0 wt% material.
• the MW Ratio of each temperature is defined as the MW (Temperature) divided by MW (Highest Temperature Fraction).
• Puncture Puncture is measured on an Instron Model 4201 with Sintech Testworks
• the specimen size is 6 inch x 6 inch and 4 measurements are made to determine an average puncture value.
• the film is conditioned for 40 hours after film production and at least 24 hours in an ASTM controlled laboratory.
• a 100 lb load cell is used with a round specimen holder.
• the specimen is a 4 inch circular specimen.
• the puncture probe is a 1 ⁇ 2 inch diameter polished stainless steel ball (on a 0.25 inch rod) with a 7.5 inch maximum travel length. There is no gauge length; the probe is as close as possible to, but not touching, the specimen.
• the crosshead speed used is 10
• the thickness is measured in the middle of the specimen.
• the thickness of the film, the distance the crosshead traveled, and the peak load are used to determine the puncture by the software.
• the puncture probe is cleaned using a "Kim-wipe" after each specimen.
• Shrink tension is measured according to the method described in Y. Jin, T. Hermel- Davidock, T. Karjala, M. Demirors, J. Wang, E. Leyva, and D. Alien, "Shrink Force Measurement of Low Shrink Force Films", SPE ANTEC Proceedings, p. 1264 (2008).
• % Free Shrink A single layer square film with a dimension of 10.16 cm x 10.16 cm is cut out by a punch press from a film sample along the edges of the machine direction (MD) and the cross direction (CD). The film is then placed in a film holder and the film holder is immersed in a hot-oil bath at 150 °C for 30 seconds. The holder is then removed from the oil bath. After oil is drained out, the length of film is measured at multiple locations in each direction and the average is taken as the final length. The % free shrink is determined from the following equation.

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• 2010
  • 2010-09-29 ES ES10761115.4T patent/ES2581568T3/es active Active
  • 2010-09-29 MY MYPI2013000664A patent/MY163384A/en unknown
  • 2010-09-29 WO PCT/US2010/050745 patent/WO2012044291A1/en active Application Filing
  • 2010-09-29 US US13/816,665 patent/US8921500B2/en not_active Expired - Fee Related
  • 2010-09-29 KR KR1020137008068A patent/KR20130098353A/ko not_active Application Discontinuation
  • 2010-09-29 CN CN201080070360.9A patent/CN103228685B/zh not_active Expired - Fee Related
  • 2010-09-29 MX MX2013003504A patent/MX342378B/es active IP Right Grant
  • 2010-09-29 BR BR112013006985-6A patent/BR112013006985A2/pt not_active Application Discontinuation
  • 2010-09-29 RU RU2013119686/04A patent/RU2013119686A/ru not_active Application Discontinuation
  • 2010-09-29 JP JP2013531544A patent/JP5775591B2/ja not_active Expired - Fee Related
  • 2010-09-29 EP EP10761115.4A patent/EP2621969B1/en not_active Not-in-force
• 2011
  • 2011-09-28 TW TW100134971A patent/TW201223967A/zh unknown
  • 2011-09-28 AR ARP110103566A patent/AR083193A1/es active IP Right Grant

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